But don't be dismayed by this alphabet soup. Just a few varieties are in day-to-day use. Also, brands are inclined to stop these overly geeky monikers in favor of more descriptive names alluding to A vital excellent in the filament, which include flexibility (NinjaTek's Ninjaflex and Polymaker's Polyflex, As an example) and power (Makerbot, XYZprin